The present invention is directed to ink compositions and, more specifically, the present invention relates to inks with, for example, a melting point of between about 60.degree. C. and about 150.degree.C., and preferably between about 70 to about 90.degree. C., especially useful for acoustic ink printing, processes and apparatuses, reference, for example, U.S. Pat. No. 5,121,141, U.S. Pat. No. 5,111,220, and U.S. Pat. No. 5,371,531, the disclosures of which are totally incorporated herein by reference, including especially acoustic ink processes as illustrated in a number of the above copending applications, such as an acoustic ink printer for printing images on a record medium. The inks of the present invention in embodiments can be considered (1) a phase change ink, that is, for example, an ink that changes from a liquid state to solid state in a suitable period of time, for example, from about 1 to about 100 milliseconds and preferably in less than about 10, such as from about 2 to about 7 milliseconds, and which inks contain a nonaqueous phase-change color spreading compound, or an additive, such as oxazoline compound that, for example, can fill the pores of a substrate, such as paper, and which compound has a melting point of, for example, lower than about 120.degree. C. and preferably between about 60 to about 100.degree. C., and with a low acoustic loss value of, for example, below about 100 dB/mm; (2) a nonaqueous crease improving thiourea compound or mixtures thereof with, for example, a boiling point of equal to about or higher than about 150.degree. C. (Centigrade) and more specifically with a boiling point from about 150 to about 225.degree. C., and a melting point of between about 25 to about 100.degree. C., and preferably between about 60 to about 100.degree. C., with low acoustic loss, which primarily enables a reduction or minimization of energy consumption, and which acoustic loss is below, or about equal to 60 dB/mm; (3) a gloss improving oxime compound or mixtures thereof; (4) a lightfastness component, such as a lightfastness UV absorber; (5) a lightfastness antioxidant; and (6) a colorant such as a dye, a pigment or mixtures thereof.
More specifically, the present invention is directed to phase-change acoustic ink compositions comprised of (1) a nonaqueous solid oxazoline compound with, for example, a melting point of lower than about 120.degree. C. and preferably between about 60.degree. C. and about 100.degree. C., and possessing a low acoustic loss and which acoustic loss is, for example, below about 100 dB/mm, and preferably from about 25 to about 80 dB/mm; (2) a nonaqueous thiourea compound or mixtures thereof with, for example, a melting point of between about 25.degree. C. to about 100.degree. C., and preferably between about 60.degree. C. to about 90.degree. C., and with low acoustic loss and which acoustic loss is, for example, below about 60 dB/mm, and preferably between about 5 to about 40 dB/mm; (3) a gloss improving oxime compound or mixtures thereof with a boiling point of, for example, equal to about or higher than about 150.degree. C. and lower than about 350.degree. C., preferably between about 170.degree. C. to about 220.degree. C., and a melting point of, for example, between about 25.degree. C. to about 90.degree. C. and with a low acoustic loss and which acoustic loss is, for example, below or about equal to 60 dB/mm, and preferably in the range of between about 5 to about 40 dB/mm; (4) a lightfastness compound, such as a UV absorber; (5) an antioxidant; (6) a colorant, and wherein there can be generated with such inks excellent developed images on plain and coated papers with acceptable image permanence, excellent projection efficiency on transparencies without a post fusing step, and excellent crease resistance, and wherein the inks possess acceptable, and in embodiments superior lightfast, for example about 89 to about 100 percent and superior waterfast between, for example, about 94 to about 100 percent. Moreover, in embodiments of the present invention there is enabled the elimination, or minimization of undesirable paper curl since water need not be present. When water is not present in the inks, a dryer can be avoided thereby minimizing the cost of the acoustic ink jet apparatus and process.